Showing papers by "La Trobe University published in 1981"
TL;DR: In this paper, it was shown that there are other wide classes of functions for which the pseudo-convexity of&(x) and quasiconvexeness off(x)-conditions are sufficient for optimality.
1,148 citations
TL;DR: A series of symmetrically disubstituted compounds, with substituents linked to the ring through a carbon atom, has been prepared from 2,9-dimethyl-1,10-phenanthroline as discussed by the authors.
245 citations
TL;DR: The major and trace element chemistry of phonolites containing spinel Iherzolite xenoliths from Bokkos (Nigeria), Phonolite Hill (northeastern Australia) and Heldburg (East Germany) is consistent with an origin by fractional crystallization of basanitic magmas at upper mantle pressures (10-15 kbar) as mentioned in this paper.
121 citations
TL;DR: In this article, the mean free path for inelastic electron scattering in a wide range of materials is described by a formula giving a dependence on electron energy of the form AE 0.75 where A is, however, sample-dependent.
105 citations
TL;DR: It is suggested that nitrogen limits the growth rate of H. tasmanica plants in northern Western Port during spring and early summer, but that an increase of 5 to 100 times the control level of nitrogen and phosphorus in the rhizosphere of these plants appears to have little direct effect on their growth or on standing crop during the first year of enrichment.
92 citations
87 citations
TL;DR: While open woodland Opuntia and Cactoblastis populations fluctuate around an equilibrium, pasture populations may better be described by the “hide and seek” model, with the woodland populations serving as refuges.
Abstract: Since the successful control of prickly pear cactus by Cactoblastis cactorum in Australia, populations of plants and moths have persisted at low densities in open woodland sites. A contagious egg distribution causes overcrowding of larvae on some plants but insures low levels or no attack of other plants. This prevents extinction of plants and insects. Cactoblastis moths choose plants with characteristics which may increase the success of their larvae. Field observations and cage experiments indicate that large, green cactuses near previously attacked cactuses receive more eggs. Plants which are actively photosynthesizing are also more attractive as oviposition sites. These oviposition preferences contribute to the observed contagious egg distribution.
87 citations
TL;DR: In this paper, New South Wales as terra nullius : The british denial of aboriginal land rights is discussed. But the focus is not on aboriginal rights, but the denial of Aboriginal land rights in general.
Abstract: (1981). New south Wales as terra nullius : The british denial of aboriginal land rights. Historical Studies: Vol. 19, No. 77, pp. 513-523.
74 citations
TL;DR: Moment and maximum likelihood estimates (m.l.e.'s) are investigated for nonparametric and parametric models for a single server queue observed over a random time horizon, namely, up to the nth departure epoch.
Abstract: Moment and maximum likelihood estimates (m.l.e.'s) arc investigated for nonparametric and parametric models for a single server queue observed over a random time horizon, namely, up to the nth departure epoch. Also. m.l.e's of the mean interarrival time and mean service time in anM/M/1 queue observed over a fixed time-interval are studied Limit distributions of these estimates are obtained Without imposing steady state assumptions on the queue-size or waiting time processes.
73 citations
TL;DR: Light-dependent reduction of GSSG appears to be the rate-limiting step in this reaction sequence at physiological concentrations of GSH, and the reaction was attributed to light-dependent Reduction of G SSG coupled to the reduction of dehydroascorbate.
Abstract: Glutathione dehydrogenase (EC 1.8.5.1) was partially purified from pea shoots. The pH optimum was 7.6. The K m values for GSH and dehydroascorbate were 4.4 and 0.44 millimolar, respectively. The enzyme was inhibited by iodoacetate and CuSO 4 but not significantly by ZnCl 2 or NaN 3 . Part of the total enzyme activity was associated with isolated chloroplasts. Illuminated ruptured chloroplasts, in the presence of 50 micromolar NADP(H) and substrate concentrations of GSH or GSSG, catalyzed (dehydroascorbate plus glutathione)-dependent O 2 evolution with the concomitant reduction of dehydroascorbate to ascorbate. Oxidation of ascorbate by ascorbate oxidase activity associated with the chloroplasts was relatively insignificant. ZnCl 2 inhibited (dehydroascorbate plus glutathione)-dependent O 2 evolution but not ascorbate formation. The reaction was attributed to light-dependent reduction of GSSG (involving glutathione reductase) coupled to the reduction of dehydroascorbate (involving glutathione dehydrogenase). Light-dependent reduction of GSSG appears to be the rate-limiting step in this reaction sequence at physiological concentrations of GSH.
62 citations
TL;DR: Sterile and non-sterile roots of sunflower seedlings were shown to reduce an insoluble higher oxide of Mn directly as discussed by the authors, and 12 other plant species were also capable of the same reduction.
Abstract: Sterile and non‐sterile roots of sunflower seedlings were shown to reduce an insoluble higher oxide of Mn directly. Non‐sterile roots of 12 other plant species were also shown to be capable of the same reduction.
TL;DR: In this paper, a simple analytical expression for the calculation of the inelastic scattering mean free path for electrons in free-electron-like metals has been derived on the basis of a dielectric formalism.
TL;DR: In this paper, chemical variations of fluid compositions for all but garnet core zones beyond 400 m from the contact occurred due to mixing of solutions derived from the Northern Boundary fault.
Abstract: Trends of chemical zoning in crystals of garnet, pyroxene, scheelite, and amphibole in 34 samples collected from the pluton9s contact updip to 500 m from the contact in the main ore horizon at the King Islnd scheelite (Dolphin) mine show systematic variations. Garnet cores up to 400 m from the contact are the most andradite rich, reaching values of 98 mole percent nearest the contact. Andradite values decrease systematically both for a particular part of the garnet crystals away from the contact and across individual grains to the outer edges. The mole percent andradite in core and outer core zones decreases to the 500-m mark while in the midsection and edge zones the values decrease to 400 m and then increase. A similar relationship occurs in pyroxenes, which nearest the contact contain hedenbergite values of 98 mole percent. Scheelite occurring as inclusions in garnet reach values of scheelite 65 powellites 34 for core zones nearest the pluton while scheelite interstitial to garnet have maximum values of scheelite 72 powellite 27 . Powellite contents decrease both toward the edges of individual grains and along the traverse to the 400-m mark where a reversal of trend occurs continuing to 500 m from the contact. Amphibole compositions show a linear decrease of the ratio Fe (super +2) /Fe (super +2) + Mg + Mn from 98 nearest the contact to 88 at 390 and then decreasing abruptly to 65 at 500 m.Fluid inclusion filling temperatures vary systematically in time and distance from the pluton, with a maximum near 800 degrees C for garnet midsections nearest the pluton to temperatures as low as 180 degrees C for interstitial calcite and quartz. The salinities decrease from near 65 weight percent total dissolved salts in the early formed minerals (i.e., garnet) nearest the pluton to less than 3 weight percent for later formed minerals farthest from the contact (i.e., calcite). These decreases occur out from the contact and progressively toward the end of the paragenetic sequence. Scheelite initially crystallized at higher temperatures, but interstitial scheelite precipitation occurred from a concentrated Na-K(-Ca)-Cl solution (approximately 10 molal, total dissolved salts) at temperatures of approximately 500 degrees C at the pluton9s contact to 300 degrees C at a distance of 500 m from the contact. Chemical variations of fluid compositions for all but garnet core zones beyond 400 m from the contact occurred due to mixing of solutions derived from the Northern Boundary fault. The interface between solutions which have permeated through and reacted with the developing skarn unit and those derived from the fault marks the maximum outward edge (from the pluton) of boiling of the solutions, the highest concentrations of W ore, reversals or inflection points in mineral composition profiles, and changes in the elemental ratios of constituents in the brine solutions.Hot saline solutions initially cooled to approximately 380 degrees C on entering the colder marble horizon. Flow along this horizon caused the loss of heat, dilution, and chemical change of the solution, this latter in response to both reactions with the marble and hornfelsic units as well as the precipitation of the skarn. Permeability was produced by the dissolution of CaCO 3 to produce CaCl (sub 2(aq)) and faulting. With time, thermal equilibrium was reached between the evolving fluid and the contact rocks until boiling of the solution occurred with the loss of a CO (sub 2-) -rich vapor. During this event the Northern Boundary fault was tectonically active so that primary fluid now entered the forming skarn both from the fault and the contact of the pluton. Mo-rich scheelite began to precipitate at the time of boiling. Subsequent to garnet + pyroxene crystallization, after the boiling event and contemporaneous with the crystallization of amphibole + some quartz, Mo-rich scheelite not "armored" in garnet was dissolved, redistributed, and redeposited as Mo-poor scheelite and molybdenite. This type of scheelite forms most of the ore being mined.
TL;DR: The Moina skarn as mentioned in this paper is a large-scale sandstone unit that is associated with the Bismuth-Cayman fault and contains up to 25 weight percent F; 0.6 percent Sn, 0.5 percent W and 0.2 percent Be, 27.5 % Zn and 4.5 ppm Au.
Abstract: The Moina skarn deposit, with its associated Sn-W-F veins and greisen, occurs at the margin of the Dolcoath leucogranite. The skarn occurs as a thick horizontal plate approximately one km in its longest dimension and up to 100 m thick and is separated from the granite9s upper near-horizontal contact by approximately 200 m of the Moina sandstone. The necessary plumbing system for access of mineralizing fluids is probably a series of east-west-trending tension fractures, now Sn-W quartz veins, associated with a major northwest-southeast-trending fault known as the Bismuth Creek fault. Emplacement of the granite was at shallow depths ( 80 vol % wollastonite); and (e) a granular garnet-pyroxene-vesuvianite-fluorite skarn overlying the other units. Unit (e) is relatively enriched in boron ([asymp] 600 ppm).The skarn unit carries up to 25 weight percent F; 0.6 percent Sn, 0.5 percent W, 0.2 percent Be, 27.5 percent Zn, and 4.5 ppm Au. Sn, Be, and Fe values increase toward the upper part of the skarn sequence whereas Zn, Cu, and Mo values are erratic. Secondary Zn-Cu-In-Cd-Au sulfide-amphibole alteration of the primary F-Sn-Be oxide skarn is related to the Bismuth Creek fault. When the primary wrigglite skarn is altered, Sn is largely lost from that part of the skarn.
TL;DR: The results emphasize the importance of eliminating microbial growth prior to studies of polysaccharide hydrolases which develop during the germination of barley and which are assumed to be of plant origin.
Abstract: Cellulase activity in crude extracts of germinating barley is at least five-fold higher in hulled than in hull-less cultivars. Surface sterilization of the grain prior to germination reduces cellulase to levels that are similar in all cultivars. In hulled barley most of the cellulase detected during germination is probably of microbial origin, but there is circumstantial evidence to suggest that significant activity can also be attributed to cellulases of plant origin. The micro-organisms associated with germinating grain reside largely in the hull and the major fungal species present on the hulled variety Clipper were Aureobasidium pullulans, Rhizopus stolonifer and Penicillium spp. Surface sterilization of the grain with silver nitrate, followed by steeping in a solution containing antibiotics, completely eliminated microbial growth on hull-less cultivars. After similar treatment of a hulled barley two yeasts could be detected. The results emphasize the importance of eliminating microbial growth prior to studies of polysaccharide hydrolases which develop during the germination of barley and which are assumed to be of plant origin.
TL;DR: In this paper, the Lie theory of extended groups has been applied to the three-dimensional time-independent harmonic oscillator and to the classical Kepler problem and the expected constants of motion are obtained.
Abstract: The method of the Lie theory of extended groups has recently been formulated for Hamiltonian mechanics in a manner which is consistent with the results obtained using the Newtonian equation of motion. Here the method is applied to the three-dimensional time-independent harmonic oscillator and to the classical Kepler problem. The expected constants of motion are obtained. Previously unobserved relations between generators and invariants are also noticed.
TL;DR: In aqueous solution bovine myelin basic protein has a close-to-random coil structure that is partially transformed to helix on interaction with lipids, and circular dichroism spectra have been used to follow this conformational transition.
TL;DR: Electrophysiological and ion distribution results obtained with mechanically skinned skeletal muscle fibres indicate that a Donnan equilibrium, characterized by large ionic concentration and electrical potential differences, is established between the myofibrillar space and the rest of the sarcoplasm surrounding the my ofibrils.
Abstract: We report here electrophysiological and ion distribution results obtained with mechanically skinned skeletal muscle fibres which indicate that a Donnan equilibrium, characterized by large ionic concentration and electrical potential differences, is established between the myofibrillar space and the rest of the sarcoplasm surrounding the myofibrils. The more negative electrical potential within the myofibrils (-15 to -29 mV for conditions similar to those in vivo) can strongly influence: (1) intracellular Ca2+ movements associated with contraction; (2) the location of sarcoplasmic enzymes, their substrates and products of reaction; (3) measurements of the electrical potential difference between the extra- and intracellular space and estimation of relative membrane permeabilities for certain ions.
TL;DR: The chicken exhibits asymptotic sensitivity to spatial detail (with acuity at about 1.5 c/deg) within 48 h of hatching, in contrast to the gradual visual development found for kittens, monkeys, and humans.
La Trobe University1, Boston University2, Max Planck Society3, Stanford University4, University of Illinois at Urbana–Champaign5, United States Department of Commerce6, University of New England (Australia)7, Aberystwyth University8, University of Ghana9, National and Kapodistrian University of Athens10, University of Hawaii11
TL;DR: A global study of the response of the total electron content of the ionosphere to the sudden commencement (S.C.) geomagnetic storm of 17 June 1972 is presented in this article.
TL;DR: It was concluded that low dose cocaine self-administration is significantly amplified by body weight reduction.
Abstract: The self-administration rates of four groups of eight rats for low dose cocaine (0.1 mg/kg infusion) under free feeding and 80% body weight conditions, with and without a fixed time 1 min (FT-1) food delivery schedule, were compared with those of saline reinforced animals under the same conditions. Results indicated that (1) overall, self-administration rates were significantly greater for cocaine reinforced animals, (2) significantly higher rates of cocaine self-administration occurred in body weight reduced rats and (3) the operation of FT-1 schedule neither significantly enhanced or inhibited drug intake. In the second experiment, schedule and no schedule conditions were reversed for the sixteen 80% body weight, cocaine reinforced rats. Results showed that reversing schedule and no schedule conditions produced no significant change in drug intake. It was concluded that low dose cocaine self-administration is significantly amplified by body weight reduction.
TL;DR: The need for methylcobalamin for the conversion of homocysteine to methionine and the requirement that myelin basic protein may be methylated, offer a rational explanation for the myelin lesions observed in cases of vitamin B12 deficiency where there is increasing evidence that methyl-, rather than adenosylcobalamine is required to prevent dysmyelination.
TL;DR: It is suggested that naloxone-opiate receptor interactions may depend on individual differences in attitudes to the situation, but may be potentiated by select environmental stimuli.
Abstract: Fifty-two paid volunteers participated in two separate factorial investigations of the effects of naloxone on time tolerance of and affective reactions to ischemia, as a function of the interaction between expectations of involvement in the experimental situation and experimental variables involving stress or suggestions of analgesia. Naloxoneinduced reduction in tolerance to ischemia interacted significantly with the level of involvement expectancies. The suggestion of analgesia provided no significant naloxonesaline discriminations, but there was a significant interaction between variable memory task conditions and drug effects on the time ischemia was tolerated. These findings suggest that naloxone-opiate receptor interactions may depend on individual differences in attitudes to the situation, but may be potentiated by select environmental stimuli. Analyses of the effects of treatment on affective reactions to ischemia failed to show consistent results.
TL;DR: A scheme of reaction for obelin activation by Ca2+ is presented which adequately explains the experimental observations and allows one to make accurate predictions regarding the relative obelin response under a variety of ionic conditions at room temperature.
Journal Article•
TL;DR: Analysis of the MS brain extracts after purification by affinity chromatography columns revealed that the anti-MBP activity was specifically mediated by IgG and resided in the IgG1, IgG2, and/or IgG4 subclasses.
Abstract: Autoimmunity to a neural antigen is a suspected cause of multiple sclerosis (MS), and a candidate autoantigen is myelin basic protein (MBP) Accordingly, saline extracts of brain from patients with MS and other diseases were prepared and the content of immunoglobulin (Ig) determined Antibody to MBP was measured with a highly-sensitive solid-phase radioimmunoassay using 125I-staphylococcal Protein A Anti-MBP activity was detected in brain extracts of all eleven MS patients, and in seven out of the eight brain extracts from the patients with other diseases; however the level of anti-MBP activity was significantly higher in the MS extracts (P less than 001) Analysis of the MS brain extracts after purification by affinity chromatography columns revealed that the anti-MBP activity was specifically mediated by IgG and resided in the IgG1, IgG2, and/or IgG4 subclasses
TL;DR: Both treatment groups are effective in alleviating depression, but the cognitive treatment group improved at a faster rate than the behavioral group, and a significant inverse correlation was observed at posttreatment and follow-up.
Abstract: Investigated the relative effectiveness of the behavioral and cognitive approaches to the treatment of depression using clinically depressed clients and the relationship between self-esteem and depression before and after treatment. Sixteen depressed patients matched for sex, age, and levels of depression were involved. Ss were assigned to either the cognitive or the behavioral treatment groups. Three weeks' baseline followed by 8 weeks' treatment programme was given to Ss in each group. The results of the statistical analysis show that both treatment groups are effective in alleviating depression, but the cognitive treatment group improved at a faster rate than the behavioral group. No significant correlation between self-esteem and depression was observed at baseline. However, a significant inverse correlation was observed at posttreatment and follow-up. The findings showed that both behavioral and cognitive approaches were effective in the treatment of depression. However, the cognitive approach was slightly better than the behavioral approach.
TL;DR: In this paper, Neodymium and strontium isotopic analyses from the Kalka layered basic intrusion, central Australia, are arrayed parallel to the Sr-axis of a Nd-Sr isotopic correlation diagram and are removed from the normal basaltic field.